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07-14-2021, 01:15 PM   #61
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QuoteOriginally posted by bdery Quote
Please, let's go lightly on the bold font, no need to be virtually screaming at each other.
Shouting is ALL CAPS; bold is for emphasis.

QuoteOriginally posted by bdery Quote
I think your wording (useless lenses) is stretching it. It is true that many designers now rely on the automated corrections, and compromise some aspects (often distortion and vignetting) to deliver their lenses.
Not at all. And I must say, I'm surprised you disagree with me.
I'm not talking about merely "imperfect" lenses; I'm talking about things like 6.2% barrel distortion and 12.6EV vignetting (see Canon RF 24-105mm f/4-7.1 STM IS - Review / Test Report - Analysis).
And I'm talking about automatically correcting CA so the lenses will get better reviews.

QuoteOriginally posted by bdery Quote
Naming lenses from Pentax which are imperfect without those corrections is possible. The figures are all there in the reviews. Naming useless lenses is more difficult, especially since we'd probably disagree on the definition of useless.
You are moving the goalposts; am I supposed to believe there's no difference between imperfect lenses (they all are) and lenses relying on forced software corrections?
I remember when Pentaxforums said the DA 560mm is not a full frame lens, because of a measured 1.3EV vignetting*. How the standards have changed, once other makers started software-correcting vignetting!

* obviously, I disagreed with that as well - many long lenses from other makers having similar, even higher levels of vignetting

07-15-2021, 06:35 AM   #62
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QuoteOriginally posted by house Quote
To a certain extent thats already the case. Only OEM lenses get the forced corrections right?
Yes but if e.g. Sony starts to use these forced corrections to make photos of third party lenses look really bad. They can implement "negativ corrections" to force the photos look bad even though the lense is actually really good corrected and producing good looking pictures. That would kill the third party lenses and force the customer to buy the more expensive sony lenses.

That aren't my thoughts but the thoughts of the mentioned youtuber. :-)
07-15-2021, 06:47 AM   #63
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QuoteOriginally posted by ChristianRock Quote
If the DA*11-18 has about 5% of distortion, that might be the first Pentax lens that was made with software corrections in mind.
I was asked to name one...
07-15-2021, 06:48 AM   #64
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QuoteOriginally posted by CharlySchramm Quote
Yes but if e.g. Sony starts to use these forced corrections to make photos of third party lenses look really bad. They can implement "negativ corrections" to force the photos look bad even though the lense is actually really good corrected and producing good looking pictures. That would kill the third party lenses and force the customer to buy the more expensive sony lenses.

That aren't my thoughts but the thoughts of the mentioned youtuber. :-)
Any camera manufacturer can implement a lot of things on cameras when used with third party lenses to make images look bad without having to use lens correction.
Like always over expose images several stops. Use image stabilization to add blur, introduce a long delay before the shot is captured. Always make the shots out of focus when using AF.
The sky is the limit.

But it will not take long before customers realize what the manufacturer are doing, and it will most likely hurt sales for that manufacturer.

07-15-2021, 06:52 AM   #65
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QuoteOriginally posted by CharlySchramm Quote
Yes but if e.g. Sony starts to use these forced corrections to make photos of third party lenses look really bad. They can implement "negativ corrections" to force the photos look bad even though the lense is actually really good corrected and producing good looking pictures. That would kill the third party lenses and force the customer to buy the more expensive sony lenses.

That aren't my thoughts but the thoughts of the mentioned youtuber. :-)
Nikon and Canon MIGHT (I doubt it) do that.

Sony has developed an "open" platform because they want third-parties to collaborate. And they even have a 10% interest in Tamron. So I really don't see them dong that. This sounds like FUD from that person.

QuoteOriginally posted by Kunzite Quote
Not at all. And I must say, I'm surprised you disagree with me.
I'm not talking about merely "imperfect" lenses; I'm talking about things like 6.2% barrel distortion and 12.6EV vignetting
I understand what you mean much better now. I had not seen reports about that lens. It's shameful, really.

QuoteOriginally posted by Kunzite Quote
And I'm talking about automatically correcting CA so the lenses will get better reviews.
I've never yet seen a system which completely forces the corrections to be activated, but I have not tested all systems (far from it). When reviewing a lens, I turn those off obviously. I see those corrections as bonuses, not crutches.
07-15-2021, 07:08 AM   #66
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QuoteOriginally posted by bdery Quote
I was asked to name one...
With that, I'm curious to see what the uncorrected distortion of the DA* 16-50mm will be.

But I think the point of this discussion - or at least what it is to me - is that there are reports that these mirrorless cameras - especially micro 4/3, but also the Sony E-mount to some extent - correct distortion before even recording the RAW data.

I don't think Pentax could do that because we will always be able to see the optics of the lens uncorrected through the OVF.
07-16-2021, 05:19 AM   #67
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QuoteOriginally posted by ChristianRock Quote
But I think the point of this discussion - or at least what it is to me - is that there are reports that these mirrorless cameras - especially micro 4/3, but also the Sony E-mount to some extent - correct distortion before even recording the RAW data.
The example given above illustrates a ludicrous amount of compromises involved in that particular design. I have a hard time understanding how any level of processing can correct for 12.6 EV of vignetting. That's essentially black, what information is there to get back?

That's a valid point that on DSLR you can see how the lens behaves in the viewfinder.

If some manufacturers bake corrections in the raw file, it is difficult to confirm it because the output will ALWAYS be corrected. The only way to confirm that would be to somehow control the lens electronically without having it mounted on the camera, and image its output on an external detector. That's convoluted, and really hard to achieve, especially if the mount is proprietary.

07-16-2021, 08:01 AM   #68
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QuoteOriginally posted by bdery Quote
The example given above illustrates a ludicrous amount of compromises involved in that particular design. I have a hard time understanding how any level of processing can correct for 12.6 EV of vignetting. That's essentially black, what information is there to get back?

That's a valid point that on DSLR you can see how the lens behaves in the viewfinder.

If some manufacturers bake corrections in the raw file, it is difficult to confirm it because the output will ALWAYS be corrected. The only way to confirm that would be to somehow control the lens electronically without having it mounted on the camera, and image its output on an external detector. That's convoluted, and really hard to achieve, especially if the mount is proprietary.
Whats the example lens you are referring to? Usually such extreme vignetting is only there if its removed by the distortion correction. So the distortion and vignetting correction becomes mandatory for a functioning lens. Your essentially cropping.

You could never do this to a DSLR lens as your framing would be off and the viewfinder would have black corners. The Leica q2 is pretty extreme in this regard.
07-19-2021, 05:51 AM   #69
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QuoteOriginally posted by house Quote
Whats the example lens you are referring to?
The Canon lens mentioned by Kunzite.
07-19-2021, 07:43 AM   #70
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QuoteOriginally posted by bdery Quote
The example given above illustrates a ludicrous amount of compromises involved in that particular design. I have a hard time understanding how any level of processing can correct for 12.6 EV of vignetting. That's essentially black, what information is there to get back?

That's a valid point that on DSLR you can see how the lens behaves in the viewfinder.

If some manufacturers bake corrections in the raw file, it is difficult to confirm it because the output will ALWAYS be corrected. The only way to confirm that would be to somehow control the lens electronically without having it mounted on the camera, and image its output on an external detector. That's convoluted, and really hard to achieve, especially if the mount is proprietary.
Don't you think what happens in this situation is that there is some level of distortion control combined with an auto crop combined with lightening of the corners that gets this down?

I very much doubt that you could lighten the corners 10 EVs on any camera out there without terrible noise, but if you just do some gentle cropping then your corners magically disappear. It also means your 24 mm is probably more like 27 mm, but if you are shooting jpegs, maybe you don't notice.
07-20-2021, 05:01 AM   #71
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QuoteOriginally posted by Rondec Quote
Don't you think what happens in this situation is that there is some level of distortion control combined with an auto crop combined with lightening of the corners that gets this down?
It's possible / likely. I assumed the company wouldn't cheat its users that way.
07-20-2021, 09:02 AM   #72
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They most certainly do but users aren't bothered as they are concerned with the results. As mentioned the Leica q2 is extreme but few if any seem to mind. I dont think a M lens could rely on software to the same extent though. Its about the expectations of the users.
07-21-2021, 06:46 AM   #73
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QuoteOriginally posted by Rondec Quote
Don't you think what happens in this situation is that there is some level of distortion control combined with an auto crop combined with lightening of the corners that gets this down?

I very much doubt that you could lighten the corners 10 EVs on any camera out there without terrible noise, but if you just do some gentle cropping then your corners magically disappear. It also means your 24 mm is probably more like 27 mm, but if you are shooting jpegs, maybe you don't notice.
I would expect the reviews to mention that if true.
07-21-2021, 08:00 AM   #74
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QuoteOriginally posted by bdery Quote
It's possible / likely. I assumed the company wouldn't cheat its users that way.
I wonder if there was copy issue here because ephotozine tested it on an RP and said there was about 1.6 EVs of vignetting at 24mm and f4. Unless they did the test on jpegs I have no idea what would give such a huge discrepancy. Canon RF 24-105mm f/4-7.1 IS STM Review - Performance | ePHOTOzine
07-21-2021, 08:17 AM   #75
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QuoteOriginally posted by Rondec Quote
I wonder if there was copy issue here because ephotozine tested it on an RP and said there was about 1.6 EVs of vignetting at 24mm and f4. Unless they did the test on jpegs I have no idea what would give such a huge discrepancy. Canon RF 24-105mm f/4-7.1 IS STM Review - Performance | ePHOTOzine
Even with JPG processing the numbers don’t match between the two reviewers.
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